Organometallic compound and organic light-emitting device including the same

ABSTRACT

An organometallic compound represented by Formula 1:
 
Ir(L 1 ) n (L 2 ) (3-n)   Formula 1
         wherein in Formula 1, L 1 , L 2 , and n are the same as described in the specification.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of Korean PatentApplication Nos. 10-2014-0094157, filed on Jul. 24, 2014, and10-2015-0048325, filed on Apr. 6, 2015, in the Korean IntellectualProperty Office, the disclosure of which is incorporated herein in itsentirety by reference.

BACKGROUND

1. Field

The present disclosure relates to an organometallic compound and anorganic light-emitting device including the same.

2. Description of the Related Art

Organic light emitting devices (OLEDs) are self-emission devices thathave wide viewing angles, high contrast ratios, and short responsetimes. In addition, OLEDs exhibit excellent brightness, driving voltage,and response speed characteristics, and produce full-color images.

A typical organic light-emitting device includes an anode, a cathode,and an organic layer that is disposed between the anode and the cathodeand includes an emission layer. A hole transport region may be disposedbetween the anode and the emission layer, and an electron transportregion may be disposed between the emission layer and the cathode. Holesprovided from the anode may move toward the emission layer through thehole transport region, and electrons provided from the cathode may movetoward the emission layer through the electron transport region. Theholes and the electrons are recombined in the emission layer to produceexcitons. These excitons change from an excited state to a ground state,thereby generating light.

Various types of organic light emitting devices are known. However,there still remains a need in OLEDs having low driving voltage, highefficiency, high brightness, and long lifespan.

SUMMARY

Provided are organometallic compounds and organic light-emitting devicesincluding the same.

According to an aspect, an organometallic compound is represented byFormula 1:

wherein in Formulae 1 to 3,

L₁ is a first ligand represented by Formula 2;

L₂ is a second ligand represented by Formula 3;

n is selected from 1, 2, and 3;

A₁₁ is selected from a C₆-C₆₀ cyclic group and C₁-C₆₀ heterocyclicgroup, each includes Y₁₁ as a cyclic ring member;

A₂₁ is selected from a C₆-C₆₀ cyclic group and a C₁-C₆₀ heterocyclicgroup, each includes X₂₃ and Y₂₁ as cyclic ring members;

A₂₂ is selected from a C₆-C₆₀ cyclic group and a C₁-C₆₀ heterocyclicgroup, each includes X₂₄ and Y₂₂ as cyclic ring members;

Y₁₁, Y₁₂, Y₂₁, and Y₂₂ are each independently selected from C and N;

X₁₃ is N or CR₁₃; X₁₄ is N or CR₁₄; X₁₅ is N or CR₁₅; X₁₆ is N or; X₁₇is N or CR₁₇;

X₁₈ is N or CR₁₈; and X₁₉ is N or CR₁₉;

X₂₃ is N or CR₂₃; and X₂₄ is N or CR₂₄;

R₁₁ to R₁₉, R₂₃, R₂₄, R₂₈, and R₂₉ are each independently selected froma hydrogen, a deuterium, —F, —Cl, —Br, —I, a cyano group, a substitutedor unsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₆-C₆₀ aryl group,and a substituted or unsubstituted C₁-C₆₀ heteroaryl group;

a11, a28, and a29 are each independently selected from 1, 2, 3, 4, 5,and 6;

R₁₂ and R₁₃ are optionally linked to each other via a divalent linkinggroup selected from a single bond, *—O—*′, *—S—*′, *—N(Z₁₁)—*′, and*—[C(Z₁₁)(Z₁₂)]_(b11)—*′; wherein

Z₁₁ and Z₁₂ are each independently selected from a hydrogen, adeuterium, —F, —Cl, —Br, —I, a substituted or unsubstituted C₁-C₆₀ alkylgroup, and a substituted or unsubstituted C₆-C₆₀ aryl group;

b11 is selected from 1, 2, 3, and 4;

* and *′ are each independently a binding site to a neighboring atom;

at least one substituent of the substituted C₁-C₆₀ alkyl group,substituted C₁-C₆₀ alkoxy group, substituted C₆-C₆₀ aryl group, andsubstituted C₁-C₆₀ heteroaryl group is selected from

a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, and a C₁-C₆₀ alkoxygroup;

a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkylgroup, a C₁-C₆₀ alkoxy group, and —Si(Q₁₁)(Q₁₂)(Q₁₃);

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group;

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group, each substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, aC₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, and—Si(Q₂₁)(Q₂₂)(Q₂₃); and —Si(Q₃₁)(Q₃₂)(Q₃₃);

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ are each independently selectedfrom a C₁-C₆₀ alkyl group and C₆-C₆₀ aryl group.

According to another aspect, an organic light-emitting device includes:

a first electrode;

a second electrode; and

an organic layer disposed between the first electrode and the secondelectrode,

wherein the organic layer includes an emission layer and at least oneorganometallic compound represented by Formula 1.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with the accompanying drawings in which:

FIG. 1 is a schematic cross-sectional view of an organic light-emittingdevice (OLED) according to an embodiment;

FIG. 2 is a graph of intensity (arbitrary units, a. u.) versus chemicalshift (parts per million, ppm) showing a ¹H NMR spectrum of Ligand 12according to a Synthesis Example;

FIG. 3 is a graph of abundance (number) versus time (minutes, min)showing gas chromatography mass spectrometer (GCMS) data of Ligand 12according to a Synthesis Example;

FIG. 4 is a graph of normalized intensity (arbitrary units, a. u.)versus wavelength (nanometers, nm) showing an emission curve of Compound12 according to a Synthesis Example;

FIG. 5 is a graph of intensity (arbitrary units, a. u.) versus chemicalshift (parts per million, ppm) showing a ¹H NMR spectrum of Ligand 7according to a Synthesis Example;

FIG. 6 is a graph of intensity (arbitrary units, a. u.) versus chemicalshift (parts per million, ppm) showing GCMS data of Ligand 7 accordingto a Synthesis Example;

FIG. 7 is a graph of intensity (arbitrary units, a. u.) versus chemicalshift (parts per million, ppm) showing a ¹H NMR spectrum of Ligand 8according to a Synthesis Example; and

FIG. 8 is a graph of intensity (arbitrary units, a. u.) versus chemicalshift (parts per million, ppm) showing GCMS data of Ligand 8 accordingto a Synthesis Example.

DETAILED DESCRIPTION

Reference will now be made in detail to embodiments, examples of whichare illustrated in the accompanying drawings, wherein like referencenumerals refer to like elements throughout. In this regard, the presentembodiments may have different forms and should not be construed asbeing limited to the descriptions set forth herein. Accordingly, theembodiments are merely described below, by referring to the figures, toexplain aspects of the present description. As used herein, the term“and/or” includes any and all combinations of one or more of theassociated listed items. Expressions such as “at least one of,” whenpreceding a list of elements, modify the entire list of elements and donot modify the individual elements of the list.

It will be understood that when an element is referred to as being “on”another element, it can be directly in contact with the other element orintervening elements may be present therebetween. In contrast, when anelement is referred to as being “directly on” another element, there areno intervening elements present.

It will be understood that, although the terms first, second, third etc.may be used herein to describe various elements, components, regions,layers, and/or sections, these elements, components, regions, layers,and/or sections should not be limited by these terms. These terms areonly used to distinguish one element, component, region, layer, orsection from another element, component, region, layer, or section.Thus, a first element, component, region, layer, or section discussedbelow could be termed a second element, component, region, layer, orsection without departing from the teachings of the present embodiments.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a,” “an,” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise.

It will be further understood that the terms “comprises” and/or“comprising,” or “includes” and/or “including” when used in thisspecification, specify the presence of stated features, regions,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,regions, integers, steps, operations, elements, components, and/orgroups thereof.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the exemplary term “below” can encompass both anorientation of above and below. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly.

About” or “approximately” as used herein is inclusive of the statedvalue and means within an acceptable range of deviation for theparticular value as determined by one of ordinary skill in the art,considering the measurement in question and the error associated withmeasurement of the particular quantity (i.e., the limitations of themeasurement system). For example, “about” can mean within one or morestandard deviations, or within ±30%, 20%, 10%, 5% of the stated value.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art and thepresent disclosure, and will not be interpreted in an idealized oroverly formal sense unless expressly so defined herein.

Exemplary embodiments are described herein with reference to crosssection illustrations that are schematic illustrations of idealizedembodiments. As such, variations from the shapes of the illustrations asa result, for example, of manufacturing techniques and/or tolerances,are to be expected. Thus, embodiments described herein should not beconstrued as limited to the particular shapes of regions as illustratedherein but are to include deviations in shapes that result, for example,from manufacturing. For example, a region illustrated or described asflat may, typically, have rough and/or nonlinear features. Moreover,sharp angles that are illustrated may be rounded. Thus, the regionsillustrated in the figures are schematic in nature and their shapes arenot intended to illustrate the precise shape of a region and are notintended to limit the scope of the present claims.

An organometallic compound represented by Formula 1 below:Ir(L₁)n(L₂)_((3-n))  Formula 1

The organometallic compound may include at least one cyano group as asubstituent, but is not limited thereto.

L₁ in Formula 1 is a first ligand represented by Formula 2 below:

L₂ in Formula 1 is a first ligand represented by Formula 3 below:

In some embodiments, at least one of L₁ and L₂ in Formula 1 may includeat least one cyano group as a substituent, but is not limited thereto.

In some embodiments, L₁ in Formula 1 may include at least one cyanogroup as a substituent, but is not limited thereto.

In some embodiments, L₂ in Formula 1 may include at least one cyanogroup as a substituent, but is not limited thereto.

In some embodiments, at least one selected from R₁₁ to R₁₉, R₂₃, R₂₄,R₂₈, and R₂₉ in Formulae 2 and 3 may be a cyano group, but is notlimited thereto.

In some embodiments, at least one selected from R₁₁, R₁₅, and R₂₉ inFormulae 2 and 3 may be a cyano group, but is not limited thereto.

In some embodiments, R₁₁ in Formula 2 may be a cyano group, but is notlimited thereto.

In some embodiments, R₁₅ in Formula 2 may be a cyano group, but is notlimited thereto.

In some embodiments, R₂₉ in Formula 3 may be a cyano group, but is notlimited thereto.

n in Formula 1 indicates the number of groups L₁, and n may be selectedfrom 1, 2, and 3. When n is an integer of 2 or more, groups L₁ may beidentical or different.

In some embodiments, n in Formula 1 may be selected from 2 and 3, but isnot limited thereto.

In Formulae 2 and 3, A₁₁ may be selected from a C₆-C₆₀ cyclic group anda C₁-C₆₀ heterocyclic group, each including Y₁₁ as a cyclic ring member;A₂₁ may be selected from a C₆-C₆₀ cyclic group and a C₁-C₆₀ heterocyclicgroup, each including X₂₃ and Y₂₁ as cyclic ring members; A₂₂ may beselected from a C₆-C₆₀ cyclic group and a C₁-C₆₀ heterocyclic group,each including X₂₄ and Y₂₂ as ring members.

In some embodiments, A₁₁, A₂₁, and A₂₂ in Formulae 2 and 3 may be eachindependently selected from a benzene, a naphthalene, an anthracene, aphenanthrene, a pyrrole, an imidazole, a pyrazole, a thiazole, anisothiazole, an oxazole, an isoxazole, a pyridine, a pyrazine, apyrimidine, a pyridazine, a quinoline, an isoquinoline, abenzoquinoline, a quinoxaline, a quinazoline, a benzoimidazole, abenzoxazole, an isobenzoxazole, a triazole, a tetrazole, an oxadiazole,a triazine, a pyridoindole, a pyridofuran, and a pyridothiophene, but isnot limited thereto.

In some embodiments, A₁₁ in Formula 2 may be selected from a benzene, anaphthalene, a pyrrole, an imidazole, and a pyrazole, but is not limitedthereto.

In some embodiments, A₁₁ in Formula 2 may be selected from a benzene andan imidazole, but is not limited thereto.

In some embodiments, A₂₁ and A₂₂ in Formula 2 may be each independentlyselected from a benzene, a naphthalene, a pyrrole, an imidazole, apyrazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, aquinoline, an isoquinoline, a quinoxaline, a quinazoline, a triazole,and a tetrazole, but is not limited thereto.

Y₁₁, Y₁₂, Y₂₁, and Y₂₂ in Formulae 2 and 3 may be each independentlyselected from a carbon atom (C) and nitrogen atom (N).

In some embodiments, in Formulae 2 and 3, Y₁₁ and Y₁₂ may be different,and Y₂₁ and Y₂₂ may be different, but is not limited thereto.

In some embodiments, in Formulae 2 and 3, Y₁₁ may be N, Y₁₂ may be C,Y₂₁ may be N, and Y₂₂ may be C, but is not limited thereto.

In some embodiments, in Formulae 2 and 3, Y₁₁ may be C, Y₁₂ may be N,Y₂₁ may be N, and Y₂₂ may be C, but is not limited thereto.

In Formula 2, X₁₃ may be N or CR₁₃; X₁₄ may be N or CR₁₄; X₁₅ may be Nor CR₁₅; X₁₆ may be N or CR₁₆; X₁₇ may be N or CR₁₇; X₁₈ may be N orCR₁₈; and X₁₉ may be N or CR₁₉.

In some embodiments, at least one selected from X₁₃ to X₁₉ in Formula 2may be N, but is not limited thereto.

In some embodiments, at least one selected from X₁₃ to X₁₆ in Formula 2may be N, but is not limited thereto.

In some embodiments, at least one selected from X₁₃ to X₁₅ in Formula 2may be N, but is not limited thereto.

In Formula 3, X₂₃ may be N or CR₂₃; and X₂₄ may be N or CR₂₄.

In some embodiments, X₂₃ in Formula 3 may be N, but is not limitedthereto.

R₁₁ to R₁₉, R₂₃, R₂₄, R₂₈, and R₂₉ in Formulae 2 and 3 may be eachindependently selected from a hydrogen, a deuterium, —F (a fluorogroup), —Cl (a chloro group), —Br (a bromo group), —I (an iodo group), acyano group, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₆-C₆₀ aryl group, and a substituted or unsubstitutedC₁-C₆₀ heteroaryl group;

at least one substituent of the substituted C₁-C₆₀ alkyl group,substituted C₁-C₆₀ alkoxy group, substituted C₆-C₆₀ aryl group, andsubstituted C₁-C₆₀ heteroaryl group may be selected from

a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, and a C₁-C₆₀ alkoxygroup;

a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkylgroup, a C₁-C₆₀ alkoxy group, and —Si(Q₁₁)(Q₁₂)(Q₁₃);

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group;

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group, each substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, aC₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, and—Si(Q₂₁)(Q₂₂)(Q₂₃); and

—Si(Q₃₁)(Q₃₂)(Q₃₃); wherein

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may be each independentlyselected from a C₁-C₆₀ alkyl group and C₆-C₆₀ aryl group.

In some embodiments, R₁₁ to R₁₉, R₂₃, R₂₄, R₂₈, and R₂₉ in Formulae 2and 3 may be each independently selected from a hydrogen, a deuterium,—F, —Cl, —Br, —I, a cyano group, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxygroup, a C₆-C₆₀ aryl group, and a C₁-C₆₀ heteroaryl group;

a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, and aC₁-C₆₀ heteroaryl group, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, a methyl group, an ethyl group, an-propyl group, an iso-propyl group, a n-butyl group, an iso-butylgroup, a sec-butyl group, a tert-butyl group, a methoxy group, an ethoxygroup, a tert-butoxy group, a phenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃); and

a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, and aC₁-C₆₀ heteroaryl group, each substituted with at least one selectedfrom a phenyl group, a naphthyl group, a pyridinyl group, and apyrimidinyl group, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, a methyl group, an ethyl group, a phenylgroup, a naphthyl group, a pyridinyl group, and a pyrimidinyl group;wherein

Q₃₁ to Q₃₃ may be each independently selected from a methyl group, anethyl group, an iso-propyl group, a tert-butyl group, a phenyl group,and a naphthyl group, but is not limited thereto.

In some embodiments, R₁₁ to R₁₉, R₂₃, R₂₄, R₂₈, and R₂₉ in Formulae 2and 3 may be each independently selected from a hydrogen, a deuterium,—F, —Cl, —Br, —I, a cyano group, a methyl group, an ethyl group, an-propyl group, an iso-propyl group, a n-butyl group, an iso-butylgroup, a sec-butyl group, a tert-butyl group, a phenyl group, a naphthylgroup, a pyridinyl group, and a pyrimidinyl group;

a phenyl group and a naphthyl group, each substituted with at least oneselected from a deuterium, —F, a methyl group, an ethyl group, aniso-propyl group, a tert-butyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃); and

a phenyl group and a naphthyl group, each substituted with at least oneselected from a phenyl group and a naphthyl group, each substituted withat least one selected from a deuterium, —F, —Cl, —Br, —I, a methylgroup, an ethyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group; wherein

Q₃₁ to Q₃₃ may be each independently selected from a methyl group and aphenyl group, but is not limited thereto.

In some embodiments, R₁₁ to R₁₉, R₂₃, R₂₄, R₂₈, and R₂₉ in Formulae 2and 3 may be each independently selected from a hydrogen, a deuterium,—F, —Cl, —Br, —I, a cyano group, and any group selected from Formulae5-1 to 5-7 below, but is not limited thereto:

wherein in Formulae 5-1 to 5-7,

Z₁ may be selected from a hydrogen, a deuterium, —F, a methyl group, anethyl group, an iso-propyl group, a tert-butyl group, and —Si(CH₃)₃; and

a phenyl group and a naphthyl group, each substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, a methyl group, an ethylgroup, a phenyl group, a naphthyl group, a pyridinyl group, and apyrimidinyl group;

d1 may be selected from 1, 2, 3, 4, and 5;

d2 may be selected from 1, 2, 3, 4, 5, 6, and 7; and

* indicates a binding site to a neighboring atom.

In some embodiments, R₁₁ to R₁₉, R₂₃, R₂₄, R₂₈, and R₂₉ in Formulae 2and 3 may be each independently selected from a hydrogen, a deuterium,—F, —Cl, —Br, —I, a cyano group, and any group selected from Formulae6-1 to 6-13 below, but is not limited thereto:

wherein in Formulae 6-1 to 6-13,

* indicates a binding site to a neighboring atom.

a11 in Formula 2 indicates the number of groups R₁₁, and a11 may beselected from 1, 2, 3, 4, 5, and 6. When a11 is an integer of 2 or more,groups R₁₁ may be identical or different.

In some embodiments, a11 in Formula 2 may be selected from 1, 2, and 3,but is not limited thereto.

a28 in Formula 3 indicates the number of groups R₂₈, and a28 may beselected from 1, 2, 3, 4, 5, and 6. When a28 is an integer of 2 or more,groups R₂₈ may be identical or different.

In some embodiments, a28 in Formula 2 may be selected from 1, 2, and 3,but is not limited thereto.

a29 in Formula 3 indicates the number of groups R₂₉, and a29 may beselected from 1, 2, 3, 4, 5, and 6. When a29 is an integer of 2 or more,groups R₂₉ may be identical or different.

In some embodiments, a29 in Formula 2 may be selected from 1, 2, and 3,but is not limited thereto.

R₁₂ and R₁₃ in Formula 2 may be optionally linked to each other via adivalent linking group selected from a single bond, *—O—*′, *—S—*′,*—N(Z₁₁)—*′, and *—[C(Z₁₁)(Z₁₂)]_(b11)—*′. Descriptions regarding Z₁₁,Z₁₂, and b11 will be described later in this specification.

In some embodiments, R₁₂ and R₁₃ in Formula 2 may be optionally linkedto each other via a divalent linking group selected from a single bond,

but is not limited thereto.

In some embodiments, R₁₂ and R₁₃ in Formula 2 may be optionally linkedto each other via a divalent linking group represented by

but is not limited thereto.

Z₁₁ and Z₁₂ may be each independently selected from a hydrogen, adeuterium, —F (a fluoro group), —Cl (a chloro group), —Br (a bromogroup), —I (an iodo group), a substituted or unsubstituted C₁-C₆₀ alkylgroup, and a substituted or unsubstituted C₆-C₆₀ aryl group.

At least one substituent of the substituted C₁-C₆₀ alkyl group andsubstituted C₆-C₆₀ aryl group may be selected from

a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, and a C₁-C₆₀ alkoxygroup;

a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkylgroup, a C₁-C₆₀ alkoxy group, and —Si(Q₁₁)(Q₁₂)(Q₁₃);

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group;

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group, each substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, aC₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, and—Si(Q₂₁)(Q₂₂)(Q₂₃); and

—Si(Q₃₁)(Q₃₂)(Q₃₃); wherein

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may be each independentlyselected from a C₁-C₆₀ alkyl group and C₆-C₆₀ aryl group.

In some embodiments, Z₁₁ and Z₁₂ may be each independently selected froma hydrogen, a deuterium, —F, a methyl group, an ethyl group, a phenylgroup, and a naphthyl group, but is not limited thereto.

In some embodiments, Z₁₁ and Z₁₂ may be each independently selected froma hydrogen, a deuterium, —F, a methyl group, and an ethyl group, but isnot limited thereto.

In some embodiments, Z₁₁ and Z₁₂ may be a hydrogen, but is not limitedthereto.

b11 indicates the repetitive number of moieties represented byC(Z₁₁)(Z₁₂), and b11 is selected from 1, 2, 3, and 4. When b11 is aninteger of 2 or more, moieties represented by C(Z₁₁)(Z₁₂) may beidentical or different.

In some embodiments, b11 may be selected from 1 and 2, but is notlimited thereto.

In some embodiments, b11 may be 2, but is not limited thereto.

In the Formulae above, * and *′ may be each independently a binding siteto a neighboring atom.

In some embodiments, the first ligand may be represented by Formula 2Abelow, but is not limited thereto:

wherein in Formula 2A,

A₁₁ may be selected from a C₆-C₆₀ cyclic group and C₁-C₆₀ heterocyclicgroup, each includes Y₁₁ as a cyclic ring member;

Y₁₁ and Y₁₂ may be each independently selected from a carbon atom (C)and nitrogen atom (N);

X₁₃ may be N or CR₁₃, X₁₄ may be N or CR₁₄, and X₁₅ may be N or CR₁₅;

R₁₁ to R₁₉ may be each independently selected from a hydrogen, adeuterium, —F (a fluoro group), —Cl (a chloro group), —Br (a bromogroup), —I (an iodo group), a cyano group, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₁-C₆₀alkoxy group, a substituted or unsubstituted C₆-C₆₀ aryl group, and asubstituted or unsubstituted C₁-C₆₀ heteroaryl group;

a11 may be selected from 1, 2, 3, 4, 5, and 6;

R₁₂ and R₁₃ may be optionally linked to each other via a divalentlinking group selected from a single bond, *—O—*′, *—S—*′, *—N(Z₁₁)—*′,and *—[C(Z₁₁)(Z₁₂)]_(b11)—*′; wherein

Z₁₁ and Z₁₂ may be each independently selected from a hydrogen, adeuterium, —F (a fluoro group), —Cl (a chloro group), —Br (a bromogroup), —I (an iodo group), and a substituted or unsubstituted C₁-C₆₀alkyl group;

b11 may be selected from 1, 2, 3, and 4;

* and *′ may be each independently a binding site to a neighboring atom;at least one substituent of the substituted C₁-C₆₀ alkyl group,substituted C₁-C₆₀ alkoxy group, substituted C₆-C₆₀ aryl group, andsubstituted C₁-C₆₀ heteroaryl group may be selected from

a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, and a C₁-C₆₀ alkoxygroup;

a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkylgroup, a C₁-C₆₀ alkoxy group, and —Si(Q₁₁)(Q₁₂)(Q₁₃);

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group;

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group, each substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, aC₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, and—Si(Q₂₁)(Q₂₂)(Q₂₃); and

—Si(Q₃₁)(Q₃₂)(Q₃₃); wherein

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may be each independentlyselected from a C₁-C₆₀ alkyl group and C₆-C₆₀ aryl group.

In some embodiments, X₁₅ in Formula 2A may be CR₁₅;

at least one of R₁₁ and R₁₅ may be a cyano group, but is not limitedthereto.

In some embodiments, the first ligand may be represented by at least anyone selected from Formulae 2-1 to 2-10 below, but is not limitedthereto:

wherein in Formulae 2-1 to 2-10,

R₁₁ to R₁₉ may be each independently selected from a hydrogen, adeuterium, —F (a fluoro group), —Cl (a chloro group), —Br (a bromogroup), —I (an iodo group), a cyano group, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₁-C₆₀alkoxy group, a substituted or unsubstituted C₆-C₆₀ aryl group, and asubstituted or unsubstituted C₁-C₆₀ heteroaryl group;

a11 may be selected from 1, 2, 3, 4, 5, and 6;

Z₁₁ and Z₁₂ may be each independently selected from a hydrogen, adeuterium, —F (a fluoro group), —Cl (a chloro group), —Br (a bromogroup), —I (an iodo group), and a substituted or unsubstituted C₁-C₆₀alkyl group;

b11 may be selected from 1, 2, 3, and 4;

* and *′ may be each independently a binding site to a neighboring atom;at least one substituent of the substituted C₁-C₆₀ alkyl group,substituted C₁-C₆₀ alkoxy group, substituted C₆-C₆₀ aryl group, andsubstituted C₁-C₆₀ heteroaryl group may be selected from

a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, and a C₁-C₆₀ alkoxygroup;

a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkylgroup, a C₁-C₆₀ alkoxy group, and —Si(Q₁₁)(Q₁₂)(Q₁₃);

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group;

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group, each substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, aC₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, and—Si(Q₂₁)(Q₂₂)(Q₂₃); and

—Si(Q₃₁)(Q₃₂)(Q₃₃); wherein

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may be each independentlyselected from a C₁-C₆₀ alkyl group and C₆-C₆₀ aryl group.

In some embodiments, at least one selected from R₁₁ to R₁₉ in Formulae2-1 to 2-10 may be a cyano group, but is not limited thereto.

In some embodiments, at least one selected from R₁₁ and R₁₅ in Formulae2-1 to 2-10 may be a cyano group, but is not limited thereto.

In some embodiments, at least one selected from R₁₁ and R₁₅ in Formulae2-1, 2-2, 2-4, 2-5, 2-7, and 2-8 may be a cyano group, but is notlimited thereto.

In some embodiments, the second ligand may be represented by Formula 3Abelow, but is not limited thereto:

wherein in Formula 3A,

Y₂₁ and Y₂₂ may be each independently selected from a carbon atom (C)and nitrogen atom (N);

X₂₁ may be N or CR₂₁, X₂₃ may be N or CR₂₃, and X₂₅ may be N or CR₂₅;

R₂₁ to R₂₇ may be each independently selected from a hydrogen, adeuterium, —F (a fluoro group), —Cl (a chloro group), —Br (a bromogroup), —I (an iodo group), a cyano group, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₁-C₆₀alkoxy group, a substituted or unsubstituted C₆-C₆₀ aryl group, and asubstituted or unsubstituted C₁-C₆₀ heteroaryl group;

* and *′ may be each independently a binding site to a neighboring atom;

at least one substituent of the substituted C₁-C₆₀ alkyl group,substituted C₁-C₆₀ alkoxy group, substituted C₆-C₆₀ aryl group, andsubstituted C₁-C₆₀ heteroaryl group may be selected from

a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, and a C₁-C₆₀ alkoxygroup;

a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkylgroup, a C₁-C₆₀ alkoxy group, and —Si(Q₁₁)(Q₁₂)(Q₁₃);

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group;

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group, each substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, aC₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, and—Si(Q₂₁)(Q₂₂)(Q₂₃); and

—Si(Q₃₁)(Q₃₂)(Q₃₃); wherein

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may be each independentlyselected from a C₁-C₆₀ alkyl group and C₆-C₆₀ aryl group.

In some embodiments, in Formula 3A, X₂₅ may be N or CR₂₅; R₂₅ may be acyano group, but is not limited thereto.

In some embodiments, the second ligand may be represented by Formula 3-1below, but is not limited thereto:

wherein in Formulae 3-1,

X₂₁ may be N or CR₂₁; and X₂₅ may be N or CR₂₅;

R₂₁, R₂₂, and R₂₄ to R₂₇ may be each independently selected from ahydrogen, a deuterium, —F, —Cl, —Br, —I, a cyano group, a C₁-C₆₀ alkylgroup, a C₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, and a C₁-C₆₀heteroaryl group;

a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, and aC₁-C₆₀ heteroaryl group, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, a methyl group, an ethyl group, an-propyl group, an iso-propyl group, a n-butyl group, an iso-butylgroup, a sec-butyl group, a tert-butyl group, a methoxy group, an ethoxygroup, a tert-butoxy group, a phenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃); and

a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, and aC₁-C₆₀ heteroaryl group, each substituted with at least one selectedfrom a phenyl group, a naphthyl group, a pyridinyl group, and apyrimidinyl group, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, a methyl group, an ethyl group, a phenylgroup, a naphthyl group, a pyridinyl group, and a pyrimidinyl group;

a11 may be selected from 1, 2, and 3;

* and *′ indicates a binding site to a neighboring atom.

In some embodiments, in Formula 3-1, X₂₅ may be N or CR₂₅; and R₂₅ maybe a cyano group, but is not limited thereto.

In some embodiments, the organometallic compound may be represented byany one selected from Formulae 1-1 to 1-8 below, but is not limitedthereto:

wherein in Formulae 1-1 to 1-8,

X₂₁ may be N or CR₂₁; and X₂₅ may be N or CR₂₅;

R₁₁ to R₁₉, R₂₁, R₂₂, R₂₄, and R₂₇ may be each independently selectedfrom a hydrogen, a deuterium, —F (a fluoro group), —Cl (a chloro group),—Br (a bromo group), —I (an iodo group), a cyano group, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₁-C₆₀alkoxy group, a substituted or unsubstituted C₆-C₆₀ aryl group, and asubstituted or unsubstituted C₁-C₆₀ heteroaryl group;

a11 may be selected from 1, 2, and 3.

In some embodiments, Z₁₁ and Z₁₂ may be each independently selected froma hydrogen, a deuterium, —F, a methyl group, and an ethyl group;

b11 may be selected from 1 and 2;

at least one substituent of the substituted C₁-C₆₀ alkyl group,substituted C₁-C₆₀ alkoxy group, substituted C₆-C₆₀ aryl group, andsubstituted C₁-C₆₀ heteroaryl group may be selected from

a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, and a C₁-C₆₀ alkoxygroup;

a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxy group, each substituted with atleast one selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkylgroup, a C₁-C₆₀ alkoxy group, and —Si(Q₁₁)(Q₁₂)(Q₁₃);

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group;

a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group,and a C₁-C₆₀ heteroaryl group, each substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, aC₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, and—Si(Q₂₁)(Q₂₂)(Q₂₃); and

—Si(Q₃₁)(Q₃₂)(Q₃₃);

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may be each independentlyselected from a C₁-C₆₀ alkyl group and C₆-C₆₀ aryl group.

In some embodiments, at least one selected from R₁₁ to R₁₉ in Formulae1-1 to 1-8 may be a cyano group, but is not limited thereto.

In some embodiments, the organometallic compound may be represented byany one selected from Compounds 1 to 14 below, but is not limitedthereto:

The highest occupied molecular orbital (HOMO) energy level, the lowestunoccupied molecular orbital (LUMO) energy level, energy gap, S1 energylevel, T1 energy level, T (dp*) (adiabatic condition), and spin densityof the Compounds above were evaluated by using Gaussian 09, whichperforms molecular structure optimizations by using density functionaltheory (DFT) based on B3LYP. The results are shown in Table 1 below.

TABLE 1 T1 T (dp*) T (dp*) HOMO LUMO energy gap S1 (Vertical)(Adiabatic) spin No. eV eV eV eV nm f* eV nm eV nm density 7 −5.18 −1.271.67 3.38 367 0.0037 2.89 429 2.82 439 0.191 8 −5.72 −2.01 2.24 3.08 4020.0258 2.86 433 2.82 440 0.241 9 −6.31 −2.66 1.96 3.04 408 0.0261 2.86434 2.82 440 0.287 10 −4.66 −0.80 1.77 3.16 392 0.0051 2.84 436 2.89 4280.150 11 −5.01 −1.22 2.34 3.29 377 0.1227 2.84 437 1.82 440 0.187 12−4.51 −0.44 1.55 3.54 350 0.0147 2.96 418 2.87 432 0.174 13 −4.35 −0.331.98 3.49 355 0.0178 2.94 422 2.86 433 0.168 14 −4.74 −0.66 1.91 3.53351 0.0206 2.98 416 2.89 429 0.172 f: Oscillator strength.

The organometallic compound represented by Formula 1 includes a partialstructure having high hole transport ability and a partial structurehaving high electron transport ability, and thus charge balance may beadjusted in an emission layer.

The organometallic compound represented by Formula 1 includes iridium(Ir) so as to form an octahedral structure. Thus, a possibility ofstacking may be low. Accordingly, the organometallic compoundrepresented by Formula 1 may provide an organic light-emitting devicehaving reduced shift of the emission wavelength and high stability.

A method of synthesizing the organometallic compound represented byFormula 1 may be apparent to one of ordinary skill in the art byreferring to Synthesis Examples used herein.

The organic light-emitting device may include:

a first electrode;

a second electrode; and

an organic layer disposed between the first electrode and the secondelectrode,

wherein the organic layer may include an emission layer and at least oneorganometallic compound represented by Formula 1.

The organometallic compound represented by Formula 1 may be used in anorganic layer of the light-emitting device. For example, theorganometallic compound represented by Formula 1 may act as a dopant ofan emission layer in the organic layer, but is not limited thereto.

Since the organic light-emitting device has an organic layer includingthe organometallic compound represented by Formula 1, the organiclight-emitting device may have a low driving voltage, high efficiency,high brightness, long lifespan, and high color purity characteristics.

The organic light-emitting device including the organometallic compoundmay emit deep blue light.

The organometallic compound represented by Formula 1 may be used in apair of electrodes in an organic light-emitting device. For example, theorganometallic compound represented by Formula 1 may be included in theemission layer. In this regard, the organometallic compound acts as adopant and the emission layer may further include a host (in otherwords, an amount of the organometallic compound represented by Formula 1may be smaller than an amount of the host).

As used herein, the expression the “(organic layer) includes at leastone organometallic compound” may be construed as meaning the “(organiclayer) may include one organometallic compound in a range of Formula 1or two different organometallic compounds in a range of Formula 1”.

For example, the organic layer may include only Compound 1 as theorganometallic compound. In this regard, Compound 1 may be included inthe emission layer of the organic light-emitting device. Alternatively,the organic layer may include Compound 1 and Compound 2 as theorganometallic compounds. In this regard, Compound 1 and Compound 2 maybe included in the same layer (for example, Compound 1 and Compound 2may all be included in the emission layer).

The first electrode may be anode, which is a hole injection electrode,and the second electrode may be a cathode, which is an electroninjection electrode. Alternatively, the first electrode may be acathode, which is an electron injection electrode, and the secondelectrode may be an anode, which is a hole injection electrode.

For example, the first electrode may be an anode, the second electrodemay be a cathode, and the organic layer may include:

i) a hole-transport region disposed between the first electrode and theemission layer, wherein the hole-transport region may include at leastone selected from a hole injection layer, a hole-transport layer, and anelectron blocking layer; and

ii) an electron-transport region disposed between the emission layer andthe second electrode, wherein the electron-transport region may includeat least one selected from a hole blocking layer, an electron transportlayer, and an electron injection layer.

As used herein, the term the “organic layer” refers to a single and/or aplurality of layers disposed between the first electrode and the secondelectrode in an organic light-emitting device. The “organic layer” mayinclude not only organic compounds but also organometallic complexesincluding metals.

FIG. 1 is a schematic view of an organic light-emitting device 10according to an embodiment. Hereinafter, a structure and a method ofmanufacturing the organic light-emitting device according to anembodiment will be described with reference to FIG. 1. The organiclight-emitting device 10 includes a first electrode 11, an organic layer15, and a second electrode 19, which are sequentially layered in thestated order.

A substrate may be additionally disposed under the first electrode 11 oron the second electrode 19. The substrate may be a related substratethat is used in an organic light-emitting device, such as glasssubstrate or a transparent plastic substrate, each having excellentmechanical strength, thermal stability, transparency, surfacesmoothness, ease of handling, and water repellency.

The first electrode 11 may be formed by depositing or sputtering amaterial for forming the first electrode 11 on the substrate. The firstelectrode 11 may be an anode. The material for the first electrode 11may be selected from materials with a high work function for an easyhole injection. The first electrode 11 may be a reflective electrode, asemi-transmissive electrode, or a transmissive electrode. The materialfor the first electrode 110 may be selected from indium tin oxide (ITO),indium zinc oxide (IZO), tin oxide (SnO₂), and zinc oxide (ZnO).Alternatively, the material for the first electrode 110 may be selectedfrom a metal or a metal alloy such as magnesium (Mg), aluminum (Al),aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), andmagnesium-silver (Mg—Ag).

The first electrode 11 may have a single layer structure or amulti-layer structure including two or more layers. For example, thefirst electrode 11 may have a triple-layer structure of ITO/Ag/ITO, butit is not limited thereto.

The organic layer 15 is disposed on the first electrode 11.

The organic layer 15 may include a hole transport region, an emissionlayer, and an electron transport region.

The hole transport region may be disposed between the first electrode 11and the emission layer.

The hole transport region may include at least one selected from a holeinjection layer, hole transport layer, electron blocking layer, andbuffer layer.

The hole transport region may only include a hole injection layer or ahole transport layer. Alternatively, the hole transport region mayinclude a structure in which a hole injection layer/a hole transportlayer or a hole injection layer/a hole transport layer/an electronblocking layer are sequentially layered on the first electrode 11.

When the hole transport region includes a hole injection layer, the holeinjection layer (HIL) may be formed on the first electrode 11 by usingvarious methods such as vacuum deposition, spin coating, casting, andLangmuir-Blodgett (LB) method.

When a hole injection layer is formed by vacuum deposition, for example,the vacuum deposition may be performed at a deposition temperature in arange of about 100 to about 500° C., at a vacuum degree in a range ofabout 10⁻⁸ to about 10⁻³ torr, and at a deposition rate in a range ofabout 0.01 Angstroms per second (Å/sec) to about 100 Å/sec, though theconditions may vary depending on a compound that is used as a holeinjection material and a structure and thermal properties of a desiredhole injection layer, but is not limited thereto.

When a hole injection layer is formed by spin coating, the spin coatingmay be performed at a coating rate in a range of about 2,000 revolutionsper minute (rpm) to about 5,000 rpm, and at a temperature in a range ofabout 80° C. to 200° C. for removing a solvent after the spin coating,though the conditions may vary depending on a compound that is used as ahole injection material and a structure and thermal properties of adesired HIL, but is not limited thereto.

The conditions for forming a hole transport layer and an electronblocking layer may be inferred based on the conditions for forming thehole injection layer.

The hole transport region may include at least one selected fromm-MTDATA, TDATA, 2-TNATA, NPB, 3-NPB, TPD, a spiro-TPD, a spiro-NPB,α-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA),polyaniline/dodecylbenzenesulfonic acid (Pani/DBSA),poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS),polyaniline/camphor sulfonic acid (Pani/CSA),(polyaniline)/poly(4-styrenesulfonate) (PANI/PSS), a compoundrepresented by Formula 201 below, and a compound represented by Formula202 below:

Ar₁₀₁ and Ar₁₀₂ in Formula 201 may be each independently selected from

a phenylene, a pentalenylene, an indenylene, a naphthylene, anazulenylene, a heptalenylene, an acenaphthylene, a fluorenylene, aphenalenylene, a phenanthrenylene, an anthracenylene, afluoranthenylene, a triphenylenylene, a pyrenylene, a chrysenylenylene,a naphthacenylene, a picenylene, a perylenylene, and a pentacenylene;and

a phenylene, a pentalenylene, an indenylene, a naphthylene, anazulenylene, a heptalenylene, an acenaphthylene, a fluorenylene, aphenalenylene, a phenanthrenylene, an anthracenylene, afluoranthenylene, a triphenylenylene, a pyrenylene, a chrysenylenylene,a naphthacenylene, a picenylene, a perylenylene, and a pentacenylene,each substituted with at least one selected from a deuterium, a halogenatom, a hydroxyl group, a cyano group, a nitro group, an amino group anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidor a salt thereof, a sulfonic acid or a salt thereof, a phosphoric acidor a salt thereof, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group,a C₃-C₁₀ cycloalkenyl group, a C₁-C₆₀ heterocycloalkyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, and a monovalent non-aromaticcondensed heteropolycyclic group.

In Formula 201, xa and xb may be each independently an integer of 0 to5, or 0, 1, or 2. In some embodiments, xa may be 1 and xb may be 0, butthey are not limited thereto.

In Formulae 201 and 202, R₁₀₁ to R₁₀₈, R₁₁₁ to R₁₁₉, and R₁₂₁ to R₁₂₄may be each independently selected from

a hydrogen, a deuterium, a halogen atom, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, a C₁-C₁₀ alkyl group (for example, a methyl group, an ethylgroup, a propyl group, a butyl group, a pentyl group, and a hexyl group)and a C₁-C₁₀ alkoxy group (for example, a methoxy group, an ethoxygroup, a propoxy group, a butoxy group, and a pentoxy group);

a C₁-C₁₀ alkyl group and a C₁-C₁₀ alkoxy group, each substituted with atleast one selected from a deuterium, a halogen atom, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, and a phosphoric acidgroup or a salt thereof;

a phenyl group, a naphthyl group, an anthracenyl group, a fluorenylgroup, and a pyrenyl group; and

a phenyl group, a naphthyl group, an anthracenyl group, a fluorenylgroup, and a pyrenyl group, each substituted with at least one selectedfrom a C₁-C₁₀ alkyl group and a C₁-C₁₀ alkoxy group, each substitutedwith at least one selected from a deuterium, a halogen atom, a hydroxylgroup, a cyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, and a phosphoric acidgroup or a salt thereof, but they are not limited thereto.

R₁₀₉ in Formula 201 may be one of a phenyl group, a naphthyl group, ananthracenyl group, a biphenyl group, and a pyridinyl group; and a phenylgroup, a naphthyl group, an anthracenyl group, a biphenyl group, and apyridinyl group, each substituted with at least one of a deuterium, ahalogen atom, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀ alkylgroup, and a C₁-C₂₀ alkoxy group.

In some embodiments, the compound represented by Formula 201 may berepresented by Formula 201A, but is not limited thereto:

Descriptions of R101, R111, R112, and R109 in Formula 201A are the sameas described above.

For example, the compound represented by Formula 201 and the compoundrepresented by Formula 202 may include Compounds HT1 to HT20, but theyare not limited thereto:

A thickness of the hole transport region may be in a range of about 100Angstroms (Å) to about 10,000 Å, for example, about 100 Å to about 1,000Å. When the hole transport region includes the a hole injection layerand a hole transport layer, a thickness of the hole injection layer maybe in a range of about 100 Å to about 10,000 Å, for example, about 100 Åto about 1,000 Å, a thickness of the hole transport layer may be in arange of about 50 Å to about 2,000 Å, for example, about 100 Å to about1,500 Å. When the thicknesses of the hole transport region, the holeinjection layer, and the hole transport layer are within the rangesdescribed above, satisfactory hole transporting properties may beobtained without a substantial increase in a driving voltage.

The hole transport region may further include, in addition to thementioned materials above, a charge-generating material to improveconductive properties. The charge-generating material may behomogeneously or non-homogeneously dispersed throughout the holetransport region.

The charge-generating material may be, for example, a p-dopant. Thep-dopant may be one selected from a quinone derivative, a metal oxide,and a cyano group-containing compound, but is not limited thereto. Forexample, non-limiting examples of the p-dopant are a quinone derivative,such as tetracyanoquinonedimethane (TCNQ) or2,3,5,6-tetrafluoro-tetracyano-1,4-benzoquinonedimethane (F4-TCNQ); ametal oxide, such as a tungsten oxide or a molybdenum oxide; and acompound containing a cyano group, such as Compound HT-D1 illustratedbelow, but they are not limited thereto.

The hole transport region may further include a buffer layer.

The buffer layer may compensate for an optical resonance distanceaccording to a wavelength of light emitted from the emission layer toimprove the efficiency of an organic light-emitting device.

An emission layer (EML) may be formed on the hole transport region byusing various methods, such as vacuum deposition, spin coating, casting,or an LB method. When the emission layer is formed by vacuum depositionor spin coating, deposition and coating conditions for the emissionlayer may be generally similar to the conditions for forming a holeinjection layer, though the conditions may vary depending on thecompound used.

The emission layer may include a host and a dopant and the dopant mayinclude the organometallic compound represented by Formula 1.

The host may include at least one selected from TPBi, TBADN, AND (alsoknown as “DNA”), CBP, CDBP, and TCP:

Alternatively, the host may further include a compound represented byFormula

Ar₁₁₁ and Ar₁₁₂ in Formula 301 may be each independently selected from aphenylene, a naphthylene, a phenanthrenylene, and a phenylene, anaphthylene, a phenanthrenylene, a fluorenyl group, and a pyrenylene,each substituted with at least one selected from a pyrenylene; and aphenyl group, a naphthyl group, and an anthracenyl group.

Ar₁₁₃ to Ar₁₁₆ in Formula 301 may be each independently selected from aC₁-C₁₀ alkyl group; a phenyl group, a naphthyl group, a phenanthrenylgroup and a pyrenyl group; and a phenyl group, a naphthyl group, aphenanthrenyl group, a fluorenyl group, and a pyrenyl group, eachsubstituted with at least one selected from a phenyl group, a naphthylgroup, and an anthracenyl group.

g, h, i, and j in Formula 301 may be each independently an integer of 0to 4, for example, 0, 1, or 2.

Ar₁₁₃ and Ar₁₁₆ in Formula 301 may be each independently selected from aC₁-C₁₀ alkyl group, each substituted with at least one selected from aphenyl group, a naphthyl group, and an anthracenyl group;

a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group,a phenanthrenyl group, and a fluorenyl group;

a phenyl group, a naphthyl group, an anthracenyl group, a pyrenyl group,a phenanthrenyl group, and a fluorenyl group, each substituted with atleast one selected from a deuterium, a halogen atom, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid or a salt thereof,a sulfonic acid or a salt thereof, a phosphoric acid or a salt thereof,a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a phenyl group, a naphthyl group, an anthracenylgroup, a pyrenyl group, a phenanthrenyl group, and a fluorenyl group;and

but they are not limited thereto.

Alternatively, the host may include a compound represented by Formula302:

Descriptions for Ar₁₂₂ to Ar₁₂₅ in Formula 302 may be understood byreferring to in connection with the descriptions for Ar₁₁₃ in Formula301 above.

Ar₁₂₆ and Ar₁₂₇ in Formula 302 may be each independently a C₁-C₁₀ alkylgroup (for example, a methyl group, an ethyl group, or a propyl group).

k and l in Formula 302 may be each independently an integer of 0 to 4.For example, k and l may be 0, 1, or 2.

For example, the compound represented by Formula 201 and the compoundrepresented by Formula 302 may include Compounds HT1 to HT42, but theyare not limited thereto:

When the organic light-emitting device is a full color organiclight-emitting device, the emission layer may be patterned into a redemission layer, a green emission layer, and a blue emission layer.Alternatively, the emission layer may have a structure in which the redemission layer, the green emission layer, and/or the blue emission layerare layered to emit white light or other various embodiments arepossible.

When the emission layer includes the host and the dopant, an amount ofthe dopant may be selected from in a range of about 0.01 to about 15parts by weight based on about 100 parts by weight of the host, but theamount is not limited thereto.

A thickness of the emission layer may be in a range of about 100 Å toabout 1,000 Å, for example, about 200 Å to about 600 Å. When thethickness of the emission layer is within this range, excellentlight-emission characteristics may be obtained without a substantialincrease in driving voltage.

Then, an electron transport region may be disposed on the emissionlayer.

The electron transport region may include at least one selected from ahole blocking layer, an electron transport layer, and an electroninjection layer, but is not limited thereto.

For example, the electron transport region may have a structure of ahole blocking layer/an electron transport layer/an electron injectionlayer or an electron transport layer/an electron injection layer, but itis not limited thereto. The electron transport layer may have a singlelayer structure or a multi-layer structure including two or moredifferent materials.

The conditions for forming a hole blocking layer, an electron transportlayer, and an electron injection layer may be inferred based on theconditions for forming the hole injection layer.

When the electron transport region includes an hole blocking layer, thehole blocking layer may, for example, include at least one of BCP andBphen, but is not limited thereto.

A thickness of the hole blocking layer may be in a range of about 20 Åto about 1,000 Å, for example, about 30 Å to about 300 Å. When thethickness of the hole blocking layer is within this range, excellenthole blocking characteristics may be obtained without a substantialincrease in driving voltage.

The electron transport layer may include at least one of BCP and Bphen,and may further include at least one of Alq3, Balq, TAZ, and NTAZ.

Alternatively, the electron transport layer may include at least oneselected from Compounds ET1 and ET2, but is not limited thereto.

A thickness of the electron transport layer may be in a range of about100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. Whenthe thickness of the electron transport layer is within this range,excellent hole blocking characteristics may be obtained without asubstantial increase in driving voltage.

Also, the electron transport layer may further include ametal-containing material in addition to the materials described above.

The metal-containing material may include a Li complex. The Li complexmay include, for example, Compound ET-D1 (lithium quinolate, LiQ) orET-D2.

The electron transport region may include an electron injection layer(EIL) that facilitates electron injection from the second electrode 19.

The electron injection layer may include at least one selected from,LiF, NaCl, CsF, Li₂O, and BaO.

A thickness of the electron injection layer may be in a range of about 1Å to about 100 Å, for example, about 3 Å to about 90 Å. When thethickness of the electron injection layer is within this range,excellent hole blocking characteristics may be obtained without asubstantial increase in driving voltage.

The second electrode 19 is disposed on the organic layer 15. The secondelectrode 19 may be a cathode. A material for the second electrode 19may be a material having a relatively low work function, such as ametal, an alloy, an electrically conductive compound, and a mixturethereof. Detailed examples of the material for forming the secondelectrode 19 are lithium (Li), magnesium (Mg), aluminum (Al),aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), andmagnesium-silver (Mg—Ag). Alternatively, ITO or IZO may be used to forma transmissive second electrode 19 to manufacture a top emissionlight-emitting device.

Hereinbefore, the organic light-emitting device has been described withreference to FIG. 1, but is not limited thereto.

A C₁-C₆₀ alkyl group as used herein refers to a linear or branchedaliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms.Detailed examples thereof are a methyl group, an ethyl group, a propylgroup, an isobutyl group, a sec-butyl group, a tert-butyl group, apentyl group, an iso-amyl group, and a hexyl group. A C₁-C₆₀ alkylenegroup as used herein refers to a divalent group having the samestructure as the C₁-C₆₀ alkyl group.

A C₁-C₆₀ alkoxy group as used herein refers to a monovalent grouprepresented by —OA₁₀₁ (wherein A₁₀₁ is the C₁-C₆₀ alkyl group). Detailedexamples thereof are such as a methoxy group, an ethoxy group, or anisopropyloxy group.

A C₆-C₆₀ aryl group as used herein refers to a monovalent group having acarbocyclic aromatic system having 6 to 60 carbon atoms, and a C₆-C₆₀arylene group as used herein refers to a divalent group having acarbocyclic aromatic system having 6 to 60 carbon atoms. Detailedexamples of the C₆-C₆₀ aryl group are such as a phenyl group, a naphthylgroup, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, ora chrysenyl group. When the C₆-C₆₀ aryl group and the C₆-C₆₀ arylenegroup each include two or more rings, the rings may be fused to eachother.

A C₁-C₆₀ heteroaryl group as used herein refers to a monovalent grouphaving a carbocyclic aromatic system having at least one hetero atomselected from N, O, P, and S as a ring-forming atom and 1 to 60 carbonatoms. A C₁-C₆₀ heteroarylene group as used herein refers to a divalentgroup having a carbocyclic aromatic system having at least one heteroatom selected from N, O, P, and S as a ring-forming atom and 1 to 60carbon atoms. Detailed examples of the C₁-C₆₀ heteroaryl group are apyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, and an isoquinolinylgroup. When the C₁-C₆₀ heteroaryl group and the C₁-C₆₀ heteroarylenegroup each include two or more rings, the rings may be fused to eachother.

Hereinafter, an organic light-emitting device according to an embodimentwill be described in detail with reference to Synthesis Examples andExamples, however, the present embodiment is not limited thereto. Thewording “B was used instead of A” used in describing Synthesis Examplesmeans that an amount of B used was identical to an amount of A usedbased on molar equivalence.

EXAMPLE Synthesis Example 1 Synthesis of Compound 12

1) Synthesis of Ligand 12

0.167 grams (g) (1 mmol) of carbazole, 0.322 g (2 mmol) of2-bromo-N-methylimidazole, 0.046 g (40 mol %) of benzotriazole, 0.038 g(20 mol %) of copper iodide, and 0.157 g (1.4 mmol) of potassiumtertiary-butoxide were dissolved in 6 milliliters (mL) ofdimethylsulfoxide and stirred at 135° C. for 48 hours. The reactionproduct was cooled, and water was added thereto. The extraction processwas performed by using ethyl acetate. The ethyl acetate extract wasdried by using magnesium sulfate, and then distilled under reducedpressure. The obtained brown solid was purified by silica gelchromatography (ethyl acetate and hexane were used as an eluent). As aresult, colorless solid Ligand 12 was obtained. Yield of Ligand 12 was40%. Ligand 12 was identified by ¹H NMR and GCMS, and the results areshown in FIGS. 2 and 3.

2) Synthesis of Compound 12

0.352 g (1 mmol) of IrCl₃*3H₂O and 0.615 g (2.5 mmol) of Ligand 12 wererefluxed in 90 mL of 2-ethoxyethanol and 3 mL of water for 24 hours. Thereaction product was cooled, water was added thereto, and the reactionproduct was filtered. The brown residue was washed with water severaltimes, and the residue was dried under a vacuum at 50° C. to obtain adimer. The dimer was reacted with 4 equivalents of Ligand 12 in thepresence of 2.5 equivalents of silver triflate in 2-ethoxyethanol at150° C. for 6 hours. The solvent was removed by distillation underreduced pressure, and the residue was purified by silica gelchromatography (ethyl acetate and hexane were used as an eluent), toobtain Compound 12. In a mass (MS) spectrum of the obtained Compound 12measured by matrix-assisted laser desorption/ionization massspectrometry time-of-flight (MALDI-TOF), a peak was observed at 929 m/z.Compound 12 emitted blue light having a wavelength of 427 nanometers(nm), and the results are shown in FIG. 4.

Synthesis Example 2 Synthesis of Compound 7

Ligand 7 was synthesized in the same manner as Ligand 12, except that3-cyano carbazole was used instead of carbazole. Ligand 7 was identifiedby ¹H NMR and GCMS, and the results are shown in FIGS. 5 and 6.

2) Synthesis of Compound 7

Compound 7 was synthesized in the same manner as in Synthesis ofCompound 12, except that Ligand 7 was used instead of Ligand 12. In a MSspectrum of the obtained Compound 7 measured by using MALDI-TOF, a peakwas observed at 1006 m/z.

Synthesis Example 3 Synthesis of Compound 8

1) Synthesis of Ligand 8

Ligand 8 was synthesized in the same manner as Ligand 12, except thatα-carboline was used instead of carbazole, and 3-bromobenzonitrile wasused instead of 2-bromo-N-methylimidazole. Ligand 12 was identified by¹H NMR and GCMS, and the results are shown in FIGS. 7 and 8.

2) Synthesis of Compound 8

Compound 8 was synthesized in the same manner as Compound 12, exceptthat Ligand 8 was used instead of Ligand 12. In a MS spectrum of theobtained Compound 8 measured by using MALDI-TOF, a peak was observed at997 m/z. Compound 8 was observed to have an emission peak at 464 nm.

Device Fabrication and Device Characteristic Evaluation

A transparent electrode substrate coated with ITO (indium-tin oxide) iscleaned, and the ITO is patterned with a photosensitive resin and anetchant to form an ITO pattern. Then, the ITO-patterned transparentelectrode substrate is cleaned again. The ITO glass substrate issonicated in isopropyl alcohol (IPA), cleaned, and rinsed with deionizedwater. The rinsed ITO glass substrate is treated with UV-ozone before itis used to fabricate an ITO coated glass substrate device.

The HTL, EML, and ETL are thermally deposited under vacuum of 10⁻⁷ torr.Then, a LiF electrode and an aluminum cathode are formed under vacuum.As for each layer of a phosphorescence device, the electron-transportingmaterial is 1,3,5-tri[(3-pyridyl)-phen-3-yl]benzene (TmPyPB), thehole-transporting material is1,1-bis{4-[N,N′-di(p-tolyl)amino]phenyl]cyclohexane (TAPC), and a hostmaterial for an emission layer is2,6-bis[3-(9H-carbazole-9-yl)phenyl)pyridine (26DCzPPy). The emissionlayer is a phosphorescent emission layer formed by doping the compound 8at a concentration of 6%.

The characteristics of the devices are evaluated. The evaluation isperformed by the following method.

The density-voltage (J-V) current and luminance-voltage (L-V)characteristic of the devices are measured using a Keithley 2635A meterand a Minolta CS-100A luminance meter. In addition, the EL(electroluminescence) spectrum and CIE color coordinator of the devicesare measured using a Minolta CS-1000A meter.

The EL devices have the following characteristics.

TABLE 2 EL CIE Maximum Driving λmax (x, y) at efficiency voltage (nm) 10mA ηL (cd/A) (V) Compound 8 467 0.17, 0.29 22.5 4.1

Referring to Table 2, an electroluminescence device using a compoundaccording to the embodiment has high luminance and high efficiency, andmay be operated at a low voltage.

As described above, according to the one or more of the aboveembodiments, the organometallic compound according to embodiments hasexcellent electric characteristics and thermal stability. Accordingly,an organic light-emitting device including the organometallic compoundmay have a low driving voltage, high efficiency, high brightness, longlifespan, and high color purity characteristics.

It should be understood that the exemplary embodiments described thereinshould be considered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each embodimentshould typically be considered as available for other similar featuresor aspects in other embodiments.

While one or more embodiments of the present disclosure have beendescribed with reference to the figures, it will be understood by thoseof ordinary skill in the art that various changes in form and detailsmay be made therein without departing from the spirit and scope of thepresent inventive concept as defined by the following claims.

What is claimed is:
 1. An organometallic compound represented by Formula1:

wherein in Formulae 1 to 3, L₁ is a first ligand represented by Formula2; L₂ is a second ligand represented by Formula 3, wherein L₂ includesat least one cyano group as a substituent; n is selected from 2 and 3;A₁₁ is selected from a C₆-C₆₀ cyclic group and a C₁-C₆₀ heterocyclicgroup selected from an imidazole, a pyrazole, an isothiazole, anisoxazole, a pyrazine, a pyridazine, a quinoline, an isoquinoline, abenzoquinoline, a quinoxaline, a quinazoline, a benzoimidazole, abenzoxazole, an isobenzoxazole, a triazole, a tetrazole, an oxadiazole,a triazine, a pyridoindole, a pyridofuran, and a pyridothiophene, eachcomprising Y₁₁ as a cyclic ring member; A₂₁, and A₂₂ are eachindependently selected from a naphthalene, an anthracene, aphenanthrene, a pyrrole, an imidazole, a pyrazole, a thiazole, anisothiazole, an oxazole, an isoxazole, a pyridine, a pyrazine, apyrimidine, a pyridazine, a quinoline, an isoquinoline, abenzoquinoline, a quinoxaline, a quinazoline, a benzoimidazole, abenzoxazole, an isobenzoxazole, a triazole, a tetrazole, an oxadiazole,a triazine, a pyridoindole, a pyridofuran, and a pyridothiophene; Y₁₁,Y₁₂, Y₂₁, and Y₂₂ are each independently selected from C and N; X₁₃ is Nor CR₁₃; X₁₄ is N or CR₁₄; X₁₅ is N or CR₁₅; X₁₆ is N or CR₁₆; X₁₇ is Nor CR₁₇; X₁₈ is N or CR₁₈; X₁₉ is N or CR₁₉; X₂₃ is N or CR₂₃; and X₂₄is N or CR₂₄; provided that when A₁₁ is an imidazole, X₁₃ is CR₁₃, X₁₄is CR₁₄, X₁₅ is CR₁₅, X₁₆ is CR₁₆, X₁₇ is CR₁₇, X₁₈ is CR₁₈, and X₁₉ isCR₁₉, then n in Formula 1 is 2, and the second ligand is represented byFormula 3A:

wherein in Formula 3A, Y₂₁ and Y₂₂ are each independently selected fromC and N; X₂₁ is N or CR₂₁, X₂₃ is N or CR₂₃, and X₂₅ is N or CR₂₅;provided that when Y₂₂ is C, then X₂₅ is N; provided that when X₂₅ is C,then Y₂₂ is N; R₂₁ to R₂₇ are each independently selected from ahydrogen, a deuterium, —F, —Cl, —Br, —I, a cyano group, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₁-C₆₀alkoxy group, a substituted or unsubstituted C₆-C₆₀ aryl group, and asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, wherein at leastone of R₂₁ to R₂₇ is a cyano group; * and *′ are each independently abinding site to a neighboring atom; at least one substituent of thesubstituted C₁-C₆₀ alkyl group, substituted C₁-C₆₀ alkoxy group,substituted C₆-C₆₀ aryl group, and substituted C₁-C₆₀ heteroaryl groupis selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group,and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxygroup, each substituted with at least one selected from a deuterium, —F,—Cl, —Br, —I, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, and—Si(Q₁₁)(Q₁₂)(Q₁₃); a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, and a C₁-C₆₀ heteroaryl group; a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, and a C₁-C₆₀heteroaryl group, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxygroup, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, a C₁-C₆₀ heteroaryl group, and —Si(Q₂₁)(Q₂₂)(Q₂₃); and—Si(Q₃₁)(Q₃₂)(Q₃₃), wherein Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ areeach independently selected from a C₁-C₆₀ alkyl group and a C₆-C₆₀ arylgroup; wherein in Formula 2 and 3, R₁₁ to R₁₉, R₂₃, R₂₄, R₂₈, and R₂₉are each independently selected from a hydrogen, a deuterium, —F, —Cl,—Br, —I, a cyano group, a substituted or unsubstituted C₁-C₆₀ alkylgroup, a substituted or unsubstituted C₁-C₆₀ alkoxy group, a substitutedor unsubstituted C₆-C₆₀ aryl group, and a substituted or unsubstitutedC₁-C₆₀ heteroaryl group; a11, a28, and a29 are each independentlyselected from 1, 2, 3, 4, 5, and 6; R₁₂ and R₁₃ are optionally linked toeach other via a divalent linking group selected from a single bond,*—O—*′, *—S—*′, *—N(Z₁₁)—*′, and *—[C(Z₁₁)(Z₁₂)]_(b11)—*′; wherein Z₁₁and Z₁₂ are each independently selected from a hydrogen, a deuterium,—F, —Cl, —Br, —I, a substituted or unsubstituted C₁-C₆₀ alkyl group, anda substituted or unsubstituted C₆-C₆₀ aryl group; b11 is selected from1, 2, 3, and 4; * and *′ are each independently a binding site to aneighboring atom; a11 is selected from 1, 2, and 3; * and *′ indicates abinding site to a neighboring atom; at least one substituent of thesubstituted C₁-C₆₀ alkyl group, substituted C₁-C₆₀ alkoxy group,substituted C₆-C₆₀ aryl group, and substituted C₁-C₆₀ heteroaryl groupis selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group,and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxygroup, each substituted with at least one selected from a deuterium, —F,—Cl, —Br, —I, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, and—Si(Q₁₁)(Q₁₂)(Q₁₃); a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, and a C₁-C₆₀ heteroaryl group; a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, and a C₁-C₆₀heteroaryl group, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxygroup, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, a C₁-C₆₀ heteroaryl group, and —Si(Q₂₁)(Q₂₂)(Q₂₃); and—Si(Q₃₁)(Q₃₂)(Q₃₃), wherein Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ areeach independently selected from a C₁-C₆₀ alkyl group and C₆-C₆₀ arylgroup.
 2. The organometallic compound of claim 1, wherein L₁ comprisesat least one cyano group as a substituent.
 3. The organometalliccompound of claim 1, wherein A₁₁ is selected from a benzene, anaphthalene, an anthracene, and a phenanthrene.
 4. The organometalliccompound of claim 1, wherein A₁₁ is each independently selected from abenzene and a naphthalene.
 5. The organometallic compound of claim 1,wherein A₂₁ and A₂₂ are each independently selected from a naphthalene,a pyrrole, an imidazole, a pyrazole, a pyridine, a pyrazine, apyrimidine, a pyridazine, a quinoline, an isoquinoline, a quinoxaline, aquinazoline, a triazole, and a tetrazole.
 6. The organometallic compoundof claim 1, wherein Y₁₁ and Y₁₂ are different from each other, and Y₂₁and Y₂₂ are different from each other.
 7. The organometallic compound ofclaim 1, wherein R₁₁ to R₁₉, R₂₃, R₂₄, R₂₈, and R₂₉ are eachindependently a hydrogen, a deuterium, —F, —Cl, —Br, —I, a cyano group,a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, and aC₁-C₆₀ heteroaryl group; a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, aC₆-C₆₀ aryl group, and a C₁-C₆₀ heteroaryl group, each substituted withat least one selected from a deuterium, —F, —Cl, —Br, —I, a methylgroup, an ethyl group, a n-propyl group, an iso-propyl group, a n-butylgroup, an iso-butyl group, a sec-butyl group, a tert-butyl group, amethoxy group, an ethoxy group, a tert-butoxy group, a phenyl group, anaphthyl group, a pyridinyl group, a pyrimidinyl group, and—Si(Q₃₁)(Q₃₂)(Q₃₃); and a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, aC₆-C₆₀ aryl group, and a C₁-C₆₀ heteroaryl group, each substituted withat least one selected from a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group, each substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, a methyl group, an ethylgroup, a phenyl group, a naphthyl group, a pyridinyl group, and apyrimidinyl group; wherein Q₃₁ to Q₃₃ are each independently selectedfrom a methyl group, an ethyl group, an iso-propyl group, a tert-butylgroup, a phenyl group, and a naphthyl group.
 8. The organometalliccompound of claim 1, wherein R₁₁ to R₁₉, R₂₃, R₂₄, R₂₈, and R₂₉ are eachindependently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, acyano group, a methyl group, an ethyl group, a n-propyl group, aniso-propyl group, a n-butyl group, an iso-butyl group, a sec-butylgroup, a tert-butyl group, a phenyl group, a naphthyl group, a pyridinylgroup, and a pyrimidinyl group; a phenyl group and a naphthyl group,each substituted with at least one selected from a deuterium, —F, amethyl group, an ethyl group, an iso-propyl group, a tert-butyl group,and —Si(Q₃₁)(Q₃₂)(Q₃₃); and a phenyl group and a naphthyl group, eachsubstituted with at least one selected from a phenyl group and anaphthyl group, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, a methyl group, an ethyl group, a phenylgroup, a naphthyl group, a pyridinyl group, and a pyrimidinyl group;wherein Q₃₁ to Q₃₃ are each independently selected from a methyl groupand a phenyl group.
 9. The organometallic compound of claim 1, whereinR₁₁ to R₁₉, R₂₃, R₂₄, R₂₈, and R₂₉ are each independently selected froma hydrogen, a deuterium, —F, —Cl, —Br, —I, a cyano group, and any groupselected from Formulae 6-1 to 6-13:

wherein in Formulae 6-1 to 6-13, * indicates a binding site to aneighboring atom.
 10. The organometallic compound of claim 1, whereinR₁₂ and R₁₃ are optionally linked to each other via a divalent linkinggroup selected from a single bond,

and Z₁₁ and Z₁₂ are each independently selected from a hydrogen, adeuterium, —F, a methyl group, and an ethyl group.
 11. Theorganometallic compound of claim 1, wherein the first ligand isrepresented by Formula 2A:

wherein in Formula 2A, A₁₁ is selected from a C₆-C₆₀ cyclic group and aC₁-C₆₀ heterocyclic group selected from an imidazole, a pyrazole, anisothiazole, an isoxazole, a pyrazine, a pyridazine, a quinoline, anisoquinoline, a benzoquinoline, a quinoxaline, a quinazoline, abenzoimidazole, a benzoxazole, an isobenzoxazole, a triazole, atetrazole, an oxadiazole, a triazine, a pyridoindole, a pyridofuran, anda pyridothiophene, each comprising Y₁₁ as a cyclic ring member; Y₁₁ andY₁₂ are each independently selected from C and N; X₁₃ is N or CR₁₃, X₁₄is N or CR₁₄, and X₁₅ is N or CR₁₅; R₁₁ to R₁₉ are each independentlyselected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a cyano group,a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₆-C₆₀aryl group, and a substituted or unsubstituted C₁-C₆₀ heteroaryl group;a11 is selected from 1, 2, 3, 4, 5, and 6; R₁₂ and R₁₃ are optionallylinked to each other via a divalent linking group selected from a singlebond, *—S—*′, *—N(Z₁₁)—*′, and *—[C(Z₁₁)(Z₁₂)]_(b11)—*′; wherein Z₁₁ andZ₁₂ are each independently selected from a hydrogen, a deuterium, —F,—Cl, —Br, —I, and a substituted or unsubstituted C₁-C₆₀ alkyl group; b11is selected from 1, 2, 3, and 4; * and *′ are each independently abinding site to a neighboring atom; at least one substituent of thesubstituted C₁-C₆₀ alkyl group, substituted C₁-C₆₀ alkoxy group,substituted C₆-C₆₀ aryl group, and substituted C₁-C₆₀ heteroaryl groupare selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group,and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxygroup, each substituted with at least one selected from a deuterium, —F,—Cl, —Br, —I, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, and—Si(Q₁₁)(Q₁₂)(Q₁₃); a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, and a C₁-C₆₀ heteroaryl group; a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, and a C₁-C₆₀heteroaryl group, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxygroup, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, a C₁-C₆₀ heteroaryl group, and —Si(Q₂₁)(Q₂₂)(Q₂₃); and—Si(Q₃₁)(Q₃₂)(Q₃₃); wherein Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ areeach independently selected from a C₁-C₆₀ alkyl group and C₆-C₆₀ arylgroup.
 12. The organometallic compound as claimed in claim 11, whereinX₁₅ is CR₁₅; and at least one group selected from R₁₁ and R₁₅ is a cyanogroup.
 13. The organometallic compound as claimed in claim 1, whereinthe first ligand is represented by any group selected from Formulae 2-1to 2-10:

wherein in Formulae 2-1 to 2-10, R₁₁ to R₁₉ are each independentlyselected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a cyano group,a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₆-C₆₀aryl group, and a substituted or unsubstituted C₁-C₆₀ heteroaryl group;a11 is selected from 1, 2, 3, 4, 5, and 6; Z₁₁ and Z₁₂ are eachindependently selected from a hydrogen, a deuterium, —F, —Cl, —Br, —I,and a substituted or unsubstituted C₁-C₆₀ alkyl group; b11 is selectedfrom 1, 2, 3, and 4; * and *′ are each independently a binding site to aneighboring atom; at least one substituent of the substituted C₁-C₆₀alkyl group, substituted C₁-C₆₀ alkoxy group, substituted C₆-C₆₀ arylgroup, and substituted C₁-C₆₀ heteroaryl group are selected from adeuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, and a C₁-C₆₀ alkoxygroup; a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxy group, each substitutedwith at least one selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀alkyl group, a C₁-C₆₀ alkoxy group, and —Si(Q₁₁)(Q₁₂)(Q₁₃); a C₆-C₆₀aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, and aC₁-C₆₀ heteroaryl group; a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, and a C₁-C₆₀ heteroaryl group, each substitutedwith at least one selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀alkyl group, a C₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, and—Si(Q₂₁)(Q₂₂)(Q₂₃); and —Si(Q₃₁)(Q₃₂)(Q₃₃), wherein Q₁₁ to Q₁₃, Q₂₁ toQ₂₃, and Q₃₁ to Q₃₃ are each independently selected from a C₁-C₆₀ alkylgroup and C₆-C₆₀ aryl group.
 14. The organometallic compound as claimedin claim 1, wherein the second ligand is represented by Formula 3A:

wherein in Formula 3A, Y₂₁ and Y₂₂ are each independently selected fromC and N; X₂₁ is N or CR₂₁, X₂₃ is N or CR₂₃, and X₂₅ is N or CR₂₅;provided that when Y₂₂ is C, then X₂₅ is N; provided that when X₂₅ is C,then Y₂₂ is N; R₂₁ to R₂₇ are each independently selected from ahydrogen, a deuterium, —F, —Cl, —Br, —I, a cyano group, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₁-C₆₀alkoxy group, a substituted or unsubstituted C₆-C₆₀ aryl group, and asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, wherein at leastone of R₂₁ to R₂₇ is a cyano group; * and *′ are each independently abinding site to a neighboring atom; at least one substituent of thesubstituted C₁-C₆₀ alkyl group, substituted C₁-C₆₀ alkoxy group,substituted C₆-C₆₀ aryl group, and substituted C₁-C₆₀ heteroaryl groupis selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group,and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxygroup, each substituted with at least one selected from a deuterium, —F,—Cl, —Br, —I, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, and—Si(Q₁₁)(Q₁₂)(Q₁₃); a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, and a C₁-C₆₀ heteroaryl group; a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, and a C₁-C₆₀heteroaryl group, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxygroup, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, a C₁-C₆₀ heteroaryl group, and —Si(Q₂₁)(Q₂₂)(Q₂₃); and—Si(Q₃₁)(Q₃₂)(Q₃₃), wherein Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ areeach independently selected from a C₁-C₆₀ alkyl group and a C₆-C₆₀ arylgroup.
 15. The organometallic compound as claimed in claim 1, whereinthe second ligand is represented by Formula 3-1:

wherein in Formula 3-1; X₂₁ is N or CR₂₁; X₂₅ is N or CR₂₅, R₂₁, R₂₂,and R₂₄ to R₂₇ are each independently selected from a hydrogen, adeuterium, —F, —Cl, —Br, —I, a cyano group, a C₁-C₆₀ alkyl group, aC₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, and a C₁-C₆₀ heteroaryl group,wherein at least one of R₂₁, R₂₂, and R₂₄ to R₂₇ is a cyano group; aC₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, and aC₁-C₆₀ heteroaryl group, each substituted with at least one selectedfrom a deuterium, —F, —Cl, —Br, —I, a methyl group, an ethyl group, an-propyl group, an iso-propyl group, a n-butyl group, an iso-butylgroup, a sec-butyl group, a tert-butyl group, a methoxy group, an ethoxygroup, a tert-butoxy group, a phenyl group, a naphthyl group, apyridinyl group, a pyrimidinyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃); and aC₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, and aC₁-C₆₀ heteroaryl group, each substituted with at least one selectedfrom a phenyl group, a naphthyl group, a pyridinyl group, and apyrimidinyl group, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, a methyl group, an ethyl group, a phenylgroup, a naphthyl group, a pyridinyl group, and a pyrimidinyl group; a11is selected from 1, 2, and 3; * and *′ indicates a binding site to aneighboring atom.
 16. An organic light-emitting device comprising: afirst electrode; a second electrode; and an organic layer disposedbetween the first electrode and the second electrode, wherein theorganic layer comprises an emission layer and at least oneorganometallic compounds of claim
 1. 17. The organic light-emittingdevice of claim 16, wherein the emission layer comprises theorganometallic compound of claim
 1. 18. The organometallic compound ofclaim 1, wherein Y₁₂ is carbon.
 19. An organometallic compoundrepresented by any group selected from Formulae 1-2 to 1-4 and 1-6 to1-8:

wherein in Formulae 1-2 to 1-4 and 1-6 to 1-8; X₂₁ is N or CR₂₁; and X₂₅is N; R₁₁ to R₁₉, R₂₁, R₂₂, R₂₄, and R₂₇ are each independently selectedfrom a hydrogen, a deuterium, —F, —Cl, —Br, —I, a cyano group, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₆-C₆₀aryl group, and a substituted or unsubstituted C₁-C₆₀ heteroaryl group,wherein at least one of R₂₁, R₂₂, R₂₄, and R₂₇ is a cyano group; a11 isselected from 1, 2, and 3; Z₁₁ and Z₁₂ are each independently selectedfrom a hydrogen, a deuterium, —F, a methyl group, and an ethyl group;b11 is selected from 1 and 2; at least one substituent of thesubstituted C₁-C₆₀ alkyl group, substituted C₁-C₆₀ alkoxy group,substituted C₆-C₆₀ aryl group, and substituted C₁-C₆₀ heteroaryl groupis selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group,and a C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group and a C₁-C₆₀ alkoxygroup, each substituted with at least one selected from a deuterium, —F,—Cl, —Br, —I, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxy group, and—Si(Q₁₁)(Q₁₂)(Q₁₃); a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, and a C₁-C₆₀ heteroaryl group; a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, and a C₁-C₆₀heteroaryl group, each substituted with at least one selected from adeuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, a C₁-C₆₀ alkoxygroup, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, a C₁-C₆₀ heteroaryl group, and —Si(Q₂₁)(Q₂₂)(Q₂₃); and—Si(Q₃₁)(Q₃₂)(Q₃₃); wherein Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ areeach independently selected from a C₁-C₆₀ alkyl group and a C₆-C₆₀ arylgroup.
 20. An organometallic compound selected from Compounds 3 to 6, 8to 11, 13, and 14:


21. An organometallic compound represented by

wherein in Formulae 1 to 3, L₁ is a first ligand represented by Formula2; L₂ is a second ligand represented by Formula 3, wherein L₂ includesat least one cyano group as a substituent; n is selected from 2 and 3;A₁₁ is selected from a C₆-C₆₀ cyclic group and a C₁-C₆₀ heterocyclicgroup, each comprising Y₁₁ as a cyclic ring member; A₂₁, and A₂₂ areeach independently selected from a naphthalene, an anthracene, aphenanthrene, a pyrrole, an imidazole, a pyrazole, a thiazole, anisothiazole, an oxazole, an isoxazole, a pyridine, a pyrazine, apyrimidine, a pyridazine, a quinoline, an isoquinoline, abenzoquinoline, a quinoxaline, a quinazoline, a benzoimidazole, abenzoxazole, an isobenzoxazole, a triazole, a tetrazole, an oxadiazole,a triazine, a pyridoindole, a pyridofuran, and a pyridothiophene; Y₁₁,Y₁₂, Y₂₁, and Y₂₂ are each independently selected from C and N; X₁₃ is Nor CR₁₃; X₁₄ is N or CR₁₄; X₁₅ is N or CR₁₅; X₁₆ is N or CR₁₆; X₁₇ is Nor CR₁₇; X₁₈ is N or CR₁₈; X₁₉ is N or CR₁₉; X₂₃ is N or CR₂₃; and X₂₄is N or CR₂₄; wherein at least one selected from X₁₃ to X₁₉ is nitrogen;provided that when Y₂₂ is C, then X₂₅ is N; provided that when X₂₅ is C,then Y₂₂ is N; R₁₁ to R₁₉, R₂₃, R₂₄, R₂₈, and R₂₉ are each independentlyselected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a cyano group,a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₆-C₆₀aryl group, and a substituted or unsubstituted C₁-C₆₀ heteroaryl group;a11, a28, and a29 are each independently selected from 1, 2, 3, 4, 5,and 6; R₁₂ and R₁₃ are optionally linked to each other via a divalentlinking group selected from a single bond, *—O—*′, *—S—*′, *—N(Z₁₁)—*′,and *—[C(Z₁₁)(Z₁₂)]_(b11)—*′; wherein Z₁₁ and Z₁₂ are each independentlyselected from a hydrogen, a deuterium, —F, —Cl, —Br, —I, a substitutedor unsubstituted C₁-C₆₀ alkyl group, and a substituted or unsubstitutedC₆-C₆₀ aryl group; b11 is selected from 1, 2, 3, and 4; * and *′ areeach independently a binding site to a neighboring atom; a11 is selectedfrom 1, 2, and 3; * and *′ indicates a binding site to a neighboringatom; at least one substituent of the substituted C₁-C₆₀ alkyl group,substituted C₁-C₆₀ alkoxy group, substituted C₆-C₆₀ aryl group, andsubstituted C₁-C₆₀ heteroaryl group is selected from a deuterium, —F,—Cl, —Br, —I, a C₁-C₆₀ alkyl group, and a C₁-C₆₀ alkoxy group; a C₁-C₆₀alkyl group and a C₁-C₆₀ alkoxy group, each substituted with at leastone selected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, aC₁-C₆₀ alkoxy group, and —Si(Q₁₁)(Q₁₂)(Q₁₃); a C₆-C₆₀ aryl group, aC₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, and a C₁-C₆₀ heteroarylgroup; a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthiogroup, and a C₁-C₆₀ heteroaryl group, each substituted with at least oneselected from a deuterium, —F, —Cl, —Br, —I, a C₁-C₆₀ alkyl group, aC₁-C₆₀ alkoxy group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, and—Si(Q₂₁)(Q₂₂)(Q₂₃); and —Si(Q₃₁)(Q₃₂)(Q₃₃); wherein Q₁₁ to Q₁₃, Q₂₁ toQ₂₃, and Q₃₁ to Q₃₃ are each independently selected from a C₁-C₆₀ alkylgroup and C₆-C₆₀ aryl group.